Seems an obvious question, doesn’t it? Of course, horror should be frightening, the whole point of horror is that it should scare people. Romance makes the heart flutter, action gets the adrenaline flowing, horror is meant to scare you. The idea most people have of horror films and books is like a ghost train where you get strapped down and roll down the rails, monsters springing out at every turn, jump scares and frights galore.
I would say though it doesn’t necessarily need to be.
Thinking back to some of the great horror icons, I wouldn’t say I find them frightening. Freddy from Nightmare on Elm Street belongs in the horror genre without a doubt. However, I don’t feel scared watching those films, they are fun. Dark, messed up fun but without a doubt an enjoyable watch. When I see Freddy show up, I’m not hiding behind the pillow, I can’t wait to see what outlandish death he has planned for the interchangeable teens. So, that is a great horror icon that isn’t frightening per se. Same with Jason Voorhees from Friday the 13th or Chucky. Ghostface from Scream, a 90’s horror icon, is the same. Recognisable, makes the scenes he is in, but scary? No.
Likewise, there has been quite a Stephen King revival of late. Stories like Christine, where a car comes to life and starts murdering people, are horror stories but they really aren’t frightening. Same with plenty of his stories, they are interesting, fun, horror but not scary.
Horror can be morbidly fascinating, I actually read a collection of horror love stories. One included a girl abducted by a psychopath, kept in a box for years who is eventually rescued. When she eventually escapes and returns to her normal life, she finds she needs that kind of controlled situation to be happy, a cushion from her PTSD. It was strange, almost deranged at points, horror ceartinly but none of it was frightening.
How genres are defined can be totally subjective, you might agree or not but I wanted to throw my two cents into the argument.